very nice moc, good colors good shape good over all I only have two real problems the first is more of a personal preference but I really, really hate it when people just flip masks. The second is that the arms look a bit...lanky, but if that's the look you were going for you got it perfectly.
Constructive Criticism-wise, the biggest flaw is definitely photo quality. Even though that's not part of the MOC, it is part of the page, and it's an important aspect of a MOC to fall behind on.
I love the shape of his shoulders, what with the pauldrons and system parts on his chest blending so well together texturally. My only gripe is that the system slopes stand out too much 'visually'. Make them match the armour, or make them a darker shade of grey.